ADX: a high field, high power density, Advanced Divertor test eXperiment

The MIT PSFC and collaborators are proposing an advanced divertor experiment (ADX) -- a tokamak specifically designed to address critical gaps in the world fusion research program on the pathway to FNSF/DEMO. This high field (6.5 tesla, 1.5 MA), high power density (P/S $\sim$ 1.5 MW/m$^{2})$ facility would utilize Alcator magnet technology to test innovative divertor concepts for next-step DT fusion devices (FNSF, DEMO) at reactor-level boundary plasma pressures and parallel heat flux densities while producing high performance core plasma conditions. The experimental platform would also test advanced lower hybrid current drive (LHCD) and ion-cyclotron range of frequency (ICRF) actuators and wave physics at the plasma densities and magnetic field strengths of a DEMO, with the unique ability to deploy launcher structures both on the low-magnetic-field side and the high-field side -- a location where energetic plasma-material interactions can be controlled and wave physics is most favorable for efficient current drive, heating and flow drive. This innovative experiment would perform plasma science and technology R{\&}D necessary to inform the conceptual development and accelerate the readiness-for-deployment of FNSF/DEMO -- in a timely manner, on a cost-effective research platform.